The technologies set forth in Japanese Unexamined Patent Application Publication 1-19-244732; Japanese Unexamined Patent Application Publication 2010-141654; Japanese Unexamined Patent Application Publication 1-107-209050; and Japanese Unexamined Patent Application Publication H10-047302, are known as examples of technology for monitoring or controlling the status of field devices. Moreover, the technology set forth in Japanese Unexamined Patent Application Publication H11-212901 is known as an example of a technology for recognizing correctly whether or not an electronic device is connected.
However, in the conventional technology no thought is given to including, in the scope of monitoring, the analog communication routes to which the field devices are connected when monitoring the status of the field devices.
One object of the present invention is to be able to check the status of communication through the analog communication routes to which the field devices when monitoring the status of the field devices are connected.
Note that there is no limitation to the aforementioned object, but rather being able to obtain effects in operation that are not provided by the conventional technology, which are effects in operation derived through the various structures illustrated in the form for carrying out the present invention, described below, can also be positioned as other objects of the present invention.